Electric door mat



July 21, 1959 1 H. J. OSTROW ELECTRIC DOOR MAT Filed June 11.2, 1957 2 Sheets-Sheet 1 July 21, 1959 H. J. os'rRow 2,895,159

` ELECTRIC nooR MAT v Filed June 12, 1957 l l 2 sheets-snee#l 2 o l A i Z5 l2/94 United States Patent.

2,895,159` ELECTRIC noon MAT Henry Ostrow, Palatine, Ill. ApplicationrJune 12, 1957,r Serial No. 665,251? sl claims. (cl. 1s311.)-

This inventionfrela'tes to electric door mats'for'porches,

entrance halls, or' the like,and more particularlyI toa new' and improved device provided withaplurality'ofbrushes which are automatically actuated whenav person-stepsV on theI device to remove dirtf and otherforeign matter'l from theshoes of the person;-

An important objectfoflv the present inventionis a power' actuated door mat having-means for conveying the dirt androther foreign materialremovedV from the soles of the shoes of a person standing onI the mat and means for collecting such dirt and other debris so` conveyed and which collecting means may be readily emptied period--y ically when necessary.

A further object is the provision of means forproducing air under pressure and directingVv` the air how toward the? sloesof a person stndngon thed'or mat to free dirtv and other foreign matter' from the shoes.- of the persom4 Af still further .objectl isl the provision of. al door mat having*` power" driven: brushes which arev readily. replaceablewhe'n necessaryi Stillanother objectis the provisionr of a power drivenA door' mat which isf simple and` durable' construction, ecoriornicalto manufacture, easy toinstall, andi neat and attractive in appearance.

rlhev foregoing and other importantA objects` and desirable features inherentin andencompassed bythe' inven tion, together with many ofthe purposes and usesthereof will becone' readily apparent'from a reading ofthe'ensuin'g'desc'ription inconjunction-'with the annexed? drawingsyin which,

v Figure 1f isA a-perspectiveivie'w of a door matembodyf Figure li'san enlarged, detailed view of certainfof the` components illustrated in Figure 6 in their assembled relationship;` I Y 7 is a fragmentary viewjof the push button for controlling the operation of the electric motor;l I

Figure' 81' isl an enlarged fragmentary? view of one end off a brush; and y Figure" 9i i fa sectional view taken substantially along line 91-9' of Figure 4; i

Referring to the drawings in detail, wherein like refer'e'rijcep charactersrepresent like elements throughout the various views, Vthereis shown open* top metal support frame 10 having spaced apart and substantially parallel vertical sidewalls 11, 112 and a hat bottom wall 113i The fr'ameA 10 may be'suitahly xedft the .top surface of entry wayk llooring as illustrated in Figure 1, or, optionally, recessed in an opening in the flooring. One end wall 14 2,895,159 Patented July 21, 1959 vice 2 of.r the frame 10"isdisposed substantially at right angles tothe side walls 11, 12 While the other wall 15 extends from' one end of the side wall 12 at an interior angle greater than Telescoped within the framev 10 is a grid frame' 27 having vertically arrangedv side walls 28, 29 adjacent the side walls 11 and 12 respectively, and vertically arranged end walls 30, 31 adjacent the end walls 14 and 1S respectively, oftheframe 10. That portion 32 of the top wall 33 of the gridV frame 27 overlyingthe compartment 25 is -provided with aplurality ofl elongated slots 34 which are arranged parallelr to the side walls 28, 29 and are spaced with respect to each other. A metal plate 35 depends from andiisrigidly fastened to the underside of the top'w'all 33 between each-pair of adjacent slots 314,

as best illustrated in Figure 2. The plates35 divide' the compartment into a plurality of chambers 36.

Suitably xed to the top wall 33 is bar` 19 of synthetic materialfsuch asnylon or the like. The bar 19. abuts the end wall 30. Thebar 19 is provided with a plurality of spaced, semi-'cylindrical grooves 17 in the lowermost surface 18thereof. Abar 16 of similar'material underlies the surface 18 and is fastened to the bar 19 bymeans of aplurality of bolts 20 extending through the upper bar"19-into threaded recesses formed in the lower bar.16. The lower bar 16s`is'provided'with spaced semi-cylindrical grooves 21 which are respectively concentric with the grooves 17 of bar 19; Each-pairv of concentric grooves 17',A 2-1`1dene a' bfearingfor slidably androtatably supporting oneend of a4v brush shaft 22'.` The oppositeends ofthe shafts 22f aresimilarly supportedY by' azlower bar 23 and an upper4 bar 24 which are spacedfrom andsubstantially parallel` tothe bars 16, 19. The upper bar 24 andthe lower bar 23 attached thereto serve as a. common wall for a pairof adjacent compartments 25, 26, as illustrated in Figures 3L and 4;

Thel shafts 22l carry cylindrical brushes 37' andthe brush on each shaft is located. in aseparate chamber 36 as shown. One end portionof'each shaft 22'. extends into th'ecompartment 26*v and the terminal end 37 thereofY is in the-formof` a cone, as shown in Figures 8`and 9L The'compartment 26 has its top completely covered by a portion 38l ofthe` top wall 33 of the grid` frame 27'and is -imperforatel except for a circular opening 39- adjacent the intersection ofthe. walls 29'and. 31. Positioned over theV opening 39'isan open-ended, upright cylindrical casing section 40-which is securely fastened to the wall portion 38'. AnY electric motor 41? is mounted in the upper portion of the casingV section 40. 'I'he driven shaft 42 of themotor 41 is' vertically disposed andi has an exhaust blower43 attached to the lowermost end thereof. Keyed to theV blower '43 and depending therefrom intothe compartment 26 isa short shaft 44 to which a belt pulley 45 is lixed. AnV upper cylindrical section 46 has one end detachably connected to uppermost end of the cylindrical section 40 by any suitable means. A plate 47 is. secured to the interior of' the sectionv 46 by any suitable means. Plate 47 is secured' to the interior of the section 46 adjacent the lower end. thereof which is provided with a central opening: 48 encircled by an annular upwardly projecting collar 49. A dir-t and dust collector -ba-g 50`- has its open end provided with a metal band 51 which` is adapted to telescope over the collar 49. A bayonet-type of' connection, indicated generally by numeral 52 is employed to detachably connect the bag 50 to the plate 47.

The uppermost end of the cylindrical section 46 has a detachable cover 53 fastened thereto. The cover 53` has an air-directing nozzle 54 mounted on. the top thereof which is in. air communication with the interior of the upper cylindrical casing section 46. The purpose of the nozzle 54 will be pointed out hereinafter.

Disposed within the compartment 26 and having its providing the unique coupling ldescribed above the is a crankshaft 55 which has its opposite ends journaled g in bearing blocks in a conventional manner. The bearing blocks are removably secured, as by bolts 56, to L-shaped v brackets 57 secured tothe side walls, 28,V 29 `of thegrid frame27. The crankshaft 55 is formed with a' plurality of oifset cranked portions 58; there being a cranked portion 58 provided for each brush shaft 2,2. `lilach cranked portion 58'extends radially in a direction substantially i;

opposite the adjacent cranked portion. The crankshaft 55 is vrotated by means of an endless belt 59 which is trained around the pulley 45 and a belt pulley 60 keyed to the crakshaft 55. It will be noted that pulley 45 is of v a much smaller diameter than kthe crankshaft pulley 60,

and, consequently, the crankshaft 55 rotates at a much lower speed than the shaft 44, which, is rotated at the speed of the armature shaft 42 of the motor 41.

A novel coupling, designated generally by numeral 61 and shown in detail in Figure 9, is employed by drivingly Yinterconnecting each shaft 22 and the crankshaft Y55 whereby rotation of the crankshaft effects reciprocation of the brush shafts. The couplings 61 are made of rubber, plastic, synthetic resin or other material having like physical properties. The couplings 61 are somewhat elongated in form and each coupling comprises an intermediate shank section 62 integrally formed with and interconnected to enlarged opposite end portions 63, 64, respectively. The enlarged end portion 63 contiguous to the bearing bars 23, 24 of each coupling 61 is provided 'with a flat face 65 which is adapted to abut a thrust washer 66 xed to the shaft 22 and axially spaced from the base of the cone-shaped terminal end 37 of the shaft 22. The enlarged end portion 63 has a central bore 67 extending axially from the iat face 65 which has an internal diameter slightly smaller than the diameter of the shaft 22 and a length slightly greater than the shaft section 68 extending between the thrust washer 66 and the base of the cone-shaped terminal end 37 when the coupling 61 is disconnected from the shaft 22. A cone shaped cavity 69, formed within the enlarged end portion 63, is in communication with one end of the bore 67 and has a volume substantially equal to the volume of the terminal end 37. From the foregoing it will be appreciated that in order to connect each shaft 22 to respective coupling 61`it is merely necessary to advance the terminal end 37 thereof axially in the bore 67 until :the terminal end 37 is disposed and seated Within the cavity 69. VWhen in this position, the iiat end face 64 j abuts therthrust washer 66 and the baseof the coneshaped terminal end 37 engages the interior wall surface defining the base of the cavity 69. VThe end 64 opposite l the end 63 is somewhat cylindrical in shape and has a central bore 70 extending therethrough which has an axis disposed substantially perpendicular to the axis of the bore 67. The axially extending section 71 of each vcranked portion 58 of the crank shaft 55 is provided `with a bearing sleeve 72 of plastic or similar material 'which is journalled thereon. Each bearing sleeve 72 is adapted to extend through the bore 70 of a respective coupling 61 and be frictionally gripped by the wall surface dening the bore 70. In order to detachably con- Aneet the couplings 61 to the crank shaft 55, a diagonal slit is provided which extends from the bore 70 through the cylindrical end 64 and part of the shank section 62 and is defined by abutting surfaces 73, 74. Thus, in order Vto attach a coupling 61' to the crank shaft 55 it is merely necessary toseparate the surfaces 73, 74 suiiciently to permit asection 71 and bearing sleeve 72 to pass therebetween and be seated in a bore 70. Thereafter, the surfaces 73, 74 are brought into abutting engagement and anv encircling, contraction band 75 is placed on the shank section 62 adjacent the cylindrical end 64 to maintam the surfaces 73,74 in engagement and the bearing Asleeve rmly gripped by the surface defining the bore 70. From the foregoing, it will be appreciated that by need` for a pivot connection between the coupling and a respective shaft end 37 is eliminated since the movement of the coupling with respect to the shaft, when the crank shaft is rotated, is accommodated by flexing of the shank section 62. It is also obvious that the pivotal connections between the couplings 61 and the crank shaft 55 require no lubrication to remain in good working order.

Electrical current for energizing the motor 41 is supplied through a conductor 76 which may be plugged into a convenience outlet located adjacent the doorway. The conductor 76leads to switch 77 fastened to the underside of portion 33 ofthe grid frame top wall 33 adjacent the vertical wall 31- and ysubstantially midway between the side walls 28, 29. The switch 77 is provided with a spring-pressed push button 78 which is biased to its circuit-opened position. Electric current is supplied to the motor 41 only when the push button 78 is depressed. The central section of a bar 79, made of spring material, is secured tothe underside of the switch 77, as shown in Figures 4 and 8. The end portions 80 of the bar 79 depend from the bottom of the switch 77 and are each provided with a terminal, flat footV 81 which is adapted to bear against the bottom wall 13 of the support frame 10. The feet 81 are vertically spaced from the underside of the switch 77, a distance `greater than the length of the push button 78 projecting from the switch 77 when in its Acircuit-opened position, as shown in Figure 4. As best Ashownin Figure 3,l the bottom edge of the end wall 3U of the grid frame 27 bears against the bottom wall 13 while the bottom edge ofL the vopposite end wall 31 is l vertically spaced above the bottom wall 13 which Vertical spacing is maintained bythe spring bar 79 when in its luncompressed state. The bottom edges of the side walls frame 27 and all the components and parts described above mounted thereon are supported by the frame 10 through the intermediary of the bottom edge of the end wall- 30 and the spring bar 79 and the resilient force exerted'by the'spring bar 79 is sufficient to maintain the top wall'33 of vthe grid frame 27 substantially parallel to the bottom wall 13 of the support frame 10 when the i door niat' is not being used. It will be noted in Figure 3 that a slight clearance is provided between the facing surfaces of the end wall 31 of the grid frame 27 and the endV wall; 15 of the support frame 10.` The clearance `is provided to accommodate pivotal movement of the grid frame 27 with respect to the support frame 10 about 515` an axis coinciding with the bottom edge of the end wall 50 and the` bottom wall 13 when weight is added to the n gridv frame '27 as when a person steps on the door mat.

The biasing action ofthe spring bar 79 is chosen such that very little additional weight is required to effect ivoting of the grid frame 27 by compressing the spring In use, when a person steps on the top wall 33 of the grid frame 27, the grid frame 27 pivots in the manner 'as pointed out hereinbefore and the push `button 78 of the switch is depressed to its circuit-closed position. Once the electric circuit is completed by depression of the ypushbutton 78, the motor 41 is energized and the brush 'shafts 22 are reciprocated. Simultaneously, with the lreciprocation of the brush lshafts 22, the exhaust blower 43A commences to operate causing a vacuum to be created in each of the chambers 36. Air communication is established betweeneach chamber 36 and compartment 26 by means` of groovesr82 formed in the bot- Y torn edgeof the lower bearing bar 23. Any dust, dirt, 'Iii etc. dislodged from the soles .of the shoes of the person standing on the door mat by the reciprocating brushes Will be drawn into the chambers `36 and the dust and dirtladen air will then pass from the compartment 26 to the collector bar 50 Where .the dust and dirt particles are retained while permitting the passage of air therethrough. The air ilowing through the bag 5) is discharged through the nozzle 54 which is directed to the feet of the person using the door mat. It will be appreciated that the current of air discharged from the nozzle facilitates removal of dirt and debris from the shoes of the person using the device. The collector bag 50 may be conveniently cleaned out periodically when required las pointed out hereinbefore. Any large particles of dirt or other debris too heavy to be drawn upwardly to the collector bag 50 by the exhaust blower 43 collect on the bottom wall 13 of the support frame 10. The bottom Wall 13 may be cleaned by merely lifting the grid frame 27 from the support frame and displacing it to one side of the support frame temporarily. lt is obvious there are no bolts or other fastening means to remove or unfasten in order to remove the grid frame 27 from the support frame 10. The brush shafts 22 may be readily replaced in the same manner. From the foregoing, it will be appreciated that the door mat is easily serviced or repaired because access to any portion of the operating mechanism is readily had simply by lifting the grid frame 27 and laying it over on its side.

When the weight of the person is -removed from the grid frame 27, the spring bar 79 pivots the grid frame 27 and the switch 77 is then opened to discontinue operation of the motor 41.

It will be noted that a plurality (two being shown in Figure l) of small apertures S3 are provided in the side wall 11 adjacent the bottom wall 13. 'Il-1e apertures 83 permit Water wh-ich may accumulate in the support frame 10 to drain therefrom.

By virtue of the novel connection between the brush shafts 22 and the couplings 61 the brush shafts 22 and the brushes 37 carried thereby may be manually rotated with respect to the grid frame 27, while being reciprocated, by user las he rubs the bottom of his shoes perpendicular to the exes of the shafts 22. Rotation of the brush shafts 22 insures even wear of the bristles of the brushes 37' and prevents the peripheral sections of the brushes 37 actually contacting the shoe soles from being overloaded and clogged with dirt by affording different sections of the brushes to extend above the grid frame 27 at will.

The embodiment of the invention chosen for the purposes of description and illustration herein is that preferred for achieving the objects of the invention and developing the utility thereof in the most desirable manner, due regard being had of existing factors of economy, simplicity of design and construction, and the improvements sought to be effected. It will be appreciated, therefore, that the particular structural and functional aspects emphasized herein are not intended to exclude, but rather to suggest, such other adaptions and modifications of the invention as fall Within the spirit and scope of the invention as defined by the appended claims.

What is claimed is:

1. A mechanical door mat comprising an opentopped, cup-shaped support frame having a flat bottom wall, transversely spaced and parallel vertical side walls, and longitudinally spaced, vertical end walls; an inverted cupshaped grid frame telescoped within said support frame having a substantially flat top wall closing the open top of said support frame having Ia plunality of elongated slots formed therethrough arranged in parallel spaced relation with respect to each other, and longitudinally spaced, vertical end walls of unequal vertical depth, the bottom edge of said end wall having the greatest vertical depth resting upon said flat bottom wall adjacent one of said end walls of said support frame; spring means depending from the opposite end of said top wall and engaging said bottom wall to maintain said top and bottom Walls substantially parallel, said spring means being effective to permit pivoting of said top wall whereby said top wall is inclined with respect -to said bottom wall; bearing means detachably connected to the underside of said top wall; a plurality of -brush shafts arranged in horizontal parallel spaced relation with respect to each other supported by said bearing means for axial and r0- tational movements separately and severally with respect to said grid frame, each of said shafts being disposed below a respective slot in said top wall; a brush having radially extending bristles carried by each shaft, a section of each brush projecting through a -respective slot and disposed above said top wall; a motor supported by said grid frame; a drive shaft rotatably supported by said grid frame and drivingly connected to said motor, said drive shaft having a plurality of axially spaced, radially oiset cranked portions; quick detachable, ilexible coupling means connecting each cranked portion to a respective brush shaft and imparting reciprocating movement to the brush shaft when said motor is energized, said coupling means permitting said brush shafts to be manually rotated; an electric circuit for energizing said motor; switch means carried by said top wall adjacent said spring means, said switch means being in said electric circuit and 'being open when said top and bottom walls are substantially parallel, said switch means being actuated to close when said top wall is inclined with respect to said bottom wall to complete said electric circuit and energize said motor; air conducting means having one end in air communication with the space between said top and bottom Walls and its opposite end opening to the atmosphere; and exhaust blower means drivingly connected to said motor and supported by said grid frame for causing air to be drawn through said slots to said space between said top and bottom walls and flow through said air conducting means and be discharged to the atmosphere.

2. A mechanical door mat .as set forth in claim 1, including nozzle means on the end of said air conducting means opening to the atmosphere for directing air discharged therefrom downwardly toward the upwardly facing surface of said top Wall.

3. A mechanical door mat as set forth in claim 2, including a detachable dirt and dust bag secured in said air conducting means for intercepting and collecting dirt and dust contained in the air ilowing through said air conducting means.

References Cited in the le of this patent UNITED STATES PATENTS 823,552 Schnell June 19, 1906 1,279,993 Cummings Sept. 24, 1918 1,361,068 Karro Dec. 7, 1920 1,952,222 Rostoker Mar. 27, 1934 2,533,781 Falloweld Dec. 12, 1950 2,647,271 Ryzenga Aug. 4, 1953 FOREIGN PATENTS 38,594 Germgiy Apr. 1, 1909 146,453 Austria Mar. 15, 1936 366,437 Italy Dec. 27, 1938 

